Connecting air conditioning lines on aircraft poses significant difficulty. Air conditioning coolant lines on aircraft are typically fabricated from copper or aluminum piping. Due to the risk of fire or explosion, the copper or aluminum piping cannot be welded while performing maintenance on an aircraft. Although flares or fittings are useful for similar applications, they have proven ineffective for aircraft cooling systems due to the leaking of such flares and fittings caused by the small molecules formed in the coolant.
Past coupler designs have been produced to connect two fluid filled lines wherein a contractible ring is seated in a circumferentially tapered channel of the coupler body. These designs employ a circumferentially tapered channel having its smallest diameter at the open end of the coupler body. Under tensile loading, such a coupler body exerts purely radial force upon the fluid filled line retained in the coupler. These radial forces may cause deformation of the coupler or the pipe, thereby causing the pipe to separate from the coupler. When compressive forces are exerted on the coupler by the fluid filled line, the contractible ring may also travel inward past the circumferentially tapered channel, causing the fluid filled line to become stuck in the coupler.
It would be desirable to provide a simple, inexpensive coupler that allowed for the sealed attachment of a pair of coolant lines in an aircraft without the risk of fire or explosion, while at the same time preventing accidental separation, over-insertion, and leaking of the coolant lines.